Comment by OneDeuxTriSeiGo

It's not literally IPFS but atproto/bluesky is using most of the bones of IPFS (IPLD) to do their entire data propagation and event broadcasting.

And tbh it shouldn't be terribly difficult to extend the existing infra to supporting a full IPFS based system but I don't think anybody has considered it worthwhile yet.

ATproto uses just the bits it immediately needs even if it could probably benefit from the other parts long term (ex for archival relay stream preservation).